Polycrystalline ferrite nano-powders, Ni1-xCuxFe2O4 (where x = 0, 0.2, 0.4, 0.6 and 0.8) were synthesized by using egg white route at 520 degrees C for 6 h, then pre-sintered and sintered into ceramics under 800 degrees C for 3 h and 900 degrees C for 3 h, respectively. X-ray diffraction, laser particle size analyzer, TEM, vibrating sample magnetometer, SEM and precision impedance analyzer were carried out to investigate phase formation, microstructural and influence of Cu content on magnetic and electrical properties of Ni-Cu ferrite samples. The results of XRD revealed that all samples were got the principal phase and there was no extra second phase except x = 0.2, the lattice parameter was found to vary from 8.337 angstrom to 8.378 angstrom, and the crystalline size was from 55.19 nm to 60.75 nm. The effect of Cu concentration on saturation magnetization and coercive force were calculated from hysteresis loop, the maximum value of saturation magnetization was 39.46 emu/g. Electrical resistivity, dielectric constant, dielectric loss tangent and permeability were measured from 10 MHz to 110 MHz. Two main contributing factors decrease the electrical properties: the reduction of the fraction of the grain boundary and the electron hopping mechanism between Fe2+ and Fe3+ ions. All results indicated that the Cu content has a significant influence on the properties. (C) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.